The automobile chassis is one of important components of a whole automobile, and the reasonability of its design determines the safety and comfort of the whole automobile. Noise is an important index for evaluating the comfort, and a bushing is assembled in a hole of a part such as a steering knuckle or a steering arm or the like in interference fit to reduce the noise and vibration. After the bushing is assembled, the part such as the steering knuckle or the like is further connected with other part, so the dimension after assembly is one of acceptance standards for evaluating whether the assembly is qualified. The dimensional requirements after some bushings are assembled are relatively strict, and the dimensions are difficult to measure with conventional measuring tools such as calipers and the like. The present disclosure can measure the dimension of a assembled bushing very conveniently and quickly.